#include <windows.h>														// Header File For Windows		
#include <gl\gl.h>															// Header File For The OpenGL32 Library
#include <gl\glu.h>	
#include <gl/glaux.h>														// Header File For The GLu32 Library
#include "gltexfont.h" //The Font Handler


/***************************************************/
/* If you want to compile this be sure to link the */
/* GLTEXFONT.LIB file included with the source!    */
/* All Credits go out to the person making the	   */
/* font library used in the source, i just can't   */
/* remember where i got it from! If you read this  */
/* and are the person who made the font handler... */
/* give me your name and i you will see your name  */
/* in the demo i am making with this stuff!        */
/*												   */
/* Hope you enjoy this snippet!					   */
/*												   */
/* Tor Erik Behrns  (tbehrns@c2i.net)			   */
/***************************************************/

HDC			hDC=NULL;														// Private GDI Device Context
HGLRC		hRC=NULL;														// Permanent Rendering Context
HWND		hWnd=NULL;														// Holds Our Window Handle
HINSTANCE	hInstance;														// Holds The Instance Of The Application
																			
bool	keys[256];															// Array Used For The Keyboard Routine
bool	active=TRUE;														// Window Active Flag Set To TRUE By Default
bool	fullscreen=TRUE;													// Fullscreen Flag Set To Fullscreen Mode By Default

typedef struct
{
	float xpos; //X Position
	float ypos; //Y Position
	float speed;//Scroll Speed
	char *lines[14]; //Number of lines in text!
	int hsize; // Text Size (Header)
	int tsize; // Text Size (Text)
	float r,g,b; //Color (Red, Green, Blue)
	float tick; //Line Spacing
} tagScroller;

tagScroller Scroll;


LRESULT	CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);						// Declaration For WndProc

void InitScroller(void)
{
	Scroll.xpos =  150.0f;
	Scroll.ypos =  0.0f;
	Scroll.speed = 0.02f;
	Scroll.hsize = 20; //Size of header
	Scroll.tsize = 10; //Size of text

	//Setting color to light blue
	Scroll.r = 0.5f;
	Scroll.g = 0.7f;
	Scroll.b = 1.0f;

	//This is the header text!
	Scroll.lines[0] = "Soft Scroller Demo"; 

	//The rest of the text in the scroller!
	Scroll.lines[1] = "This is just a little"; 
	Scroll.lines[2] = "demonstration on how"; 
	Scroll.lines[3] = "to make a verry simple"; 
	Scroll.lines[4] = "scroller with the use"; 
	Scroll.lines[5] = "of OpenGL!"; 
	Scroll.lines[6] = "---------------------"; 
	Scroll.lines[7] = "Thanks to NEHE for basecode!"; 
	Scroll.lines[8] = "This Code is free for use to"; 
	Scroll.lines[9] = "anyone! All i want is to be"; 
	Scroll.lines[10] = "mentioned in the game/demo you"; 
	Scroll.lines[11] = "might be using this code in!"; 
	Scroll.lines[12] = "--------------------"; 
	Scroll.lines[13] = "Tor Erik a.k.a XaOs"; 
	Scroll.lines[14] = "http://home.no.net/cybertux"; 

	Scroll.tick = 15.0f; //Line Spacing
	fontLoad ("font2.tga"); //Loads the Font image
}

GLvoid ReSizeGLScene(GLsizei width, GLsizei height)							// Resize And Initialize The GL Window
{																			
	if (height==0)															// Prevent A Divide By Zero By
	{																		
		height=1;															// Making Height Equal One
	}																		
																			
	glViewport(0,0,width,height);											// Reset The Current Viewport
																			
	glMatrixMode(GL_PROJECTION);											// Select The Projection Matrix
	glLoadIdentity();														// Reset The Projection Matrix

	gluPerspective(45.0f,(GLfloat)width/(GLfloat)height,0.1f,100.0f);		// Calculate The Aspect Ratio Of The Window

	glMatrixMode(GL_MODELVIEW);												// Select The Modelview Matrix
	glLoadIdentity();														// Reset The Modelview Matrix
}

int InitGL(GLvoid)															// All Setup For OpenGL Goes Here
{																			
	glShadeModel(GL_SMOOTH);												// Enable Smooth Shading
	glClearColor(0.0f, 0.0f, 0.0f, 0.5f);									// Black Background
	glClearDepth(1.0f);														// Depth Buffer Setup
	glEnable(GL_DEPTH_TEST);												// Enables Depth Testing
	glDepthFunc(GL_LEQUAL);													// The Type Of Depth Testing To Do
	glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);						// Really Nice Perspective Calculations

	//Runs the Init Function coded above!
	InitScroller();
	return TRUE;															// Initialization Went OK
}

int DrawGLScene(GLvoid)														// Here's Where We Do All The Drawing
{																			
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);						// Clear Screen And Depth Buffer
	glLoadIdentity();														// Reset The Current Modelview Matrix
	glTranslatef (0.0f, 0.0f, 0.0f);


	//This is where the header gets printed
	fontSize(20);
	//Setting the Font color
	fontColor (Scroll.r, Scroll.g, Scroll.b);
	fontDrawString ((int)Scroll.xpos,(int)Scroll.ypos,Scroll.lines[0]);


	//Run a loop for the rest of the lines in the text
	for (int i=1; i<15; i++)
	{
		//Font size
		fontSize(10);
		//Setting the Font color
		fontColor (Scroll.r, Scroll.g, Scroll.b);
		fontDrawString ((int)Scroll.xpos + 50,
						//This moves the lines downwards with the Line Spacing 
			            (int)Scroll.ypos - ((int)Scroll.tick*i) - 15, 
						//The rest of the lines
						Scroll.lines[i]);
	}
	
	//Scrolling the Ypos of the text Upwards
	Scroll.ypos += Scroll.speed;
	return TRUE;															// Everything Went OK
}

GLvoid KillGLWindow(GLvoid)													// Properly Kill The Window
{																			
	if (fullscreen)															// Are We In Fullscreen Mode?
	{																		
		ChangeDisplaySettings(NULL,0);										// If So Switch Back To The Desktop
		ShowCursor(TRUE);													// Show Mouse Pointer
	}																		
																			
	if (hRC)																// Do We Have A Rendering Context?
	{																		
		if (!wglMakeCurrent(NULL,NULL))										// Are We Able To Release The DC And RC Contexts?
		{
			MessageBox(NULL,"Release Of DC And RC Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		}

		if (!wglDeleteContext(hRC))											// Are We Able To Delete The RC?
		{
			MessageBox(NULL,"Release Rendering Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		}
		hRC=NULL;															// Set RC To NULL
	}

	if (hDC && !ReleaseDC(hWnd,hDC))										// Are We Able To Release The DC
	{
		MessageBox(NULL,"Release Device Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		hDC=NULL;															// Set DC To NULL
	}

	if (hWnd && !DestroyWindow(hWnd))										// Are We Able To Destroy The Window?
	{
		MessageBox(NULL,"Could Not Release hWnd.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		hWnd=NULL;															// Set hWnd To NULL
	}

	if (!UnregisterClass("OpenGL",hInstance))								// Are We Able To Unregister Class
	{
		MessageBox(NULL,"Could Not Unregister Class.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		hInstance=NULL;														// Set hInstance To NULL
	}
}

//////////////////////////////////////////////////////////////////////////////
// Creates The OpenGL Window
// Parameters:
//	title			- Title To Appear At The Top Of The Window
//	width			- Width Of The GL Window Or Fullscreen Mode
//	height			- Height Of The GL Window Or Fullscreen Mode
//	bits			- Number Of Bits To Use For Color (8/16/24/32)
//	fullscreenflag	- Use Fullscreen Mode (TRUE) Or Windowed Mode (FALSE)
//////////////////////////////////////////////////////////////////////////////
BOOL CreateGLWindow(char* title, int width, int height, int bits, bool fullscreenflag)
{
	GLuint		PixelFormat;												// Holds The Results After Searching For A Match
	WNDCLASS	wc;															// Windows Class Structure
	DWORD		dwExStyle;													// Window Extended Style
	DWORD		dwStyle;													// Window Style
	RECT		WindowRect;													// Grabs Rectangle Upper Left / Lower Right Values
	WindowRect.left=(long)0;												// Set Left Value To 0
	WindowRect.right=(long)width;											// Set Right Value To Requested Width
	WindowRect.top=(long)0;													// Set Top Value To 0
	WindowRect.bottom=(long)height;											// Set Bottom Value To Requested Height
																			
	fullscreen=fullscreenflag;												// Set The Global Fullscreen Flag

	hInstance			= GetModuleHandle(NULL);							// Grab An Instance For Our Window
	wc.style			= CS_HREDRAW | CS_VREDRAW | CS_OWNDC;				// Redraw On Size, And Own DC For Window.
	wc.lpfnWndProc		= (WNDPROC) WndProc;								// WndProc Handles Messages
	wc.cbClsExtra		= 0;												// No Extra Window Data
	wc.cbWndExtra		= 0;												// No Extra Window Data
	wc.hInstance		= hInstance;										// Set The Instance
	wc.hIcon			= LoadIcon(NULL, IDI_WINLOGO);						// Load The Default Icon
	wc.hCursor			= LoadCursor(NULL, IDC_ARROW);						// Load The Arrow Pointer
	wc.hbrBackground	= NULL;												// No Background Required For GL
	wc.lpszMenuName		= NULL;												// We Don't Want A Menu
	wc.lpszClassName	= "OpenGL";											// Set The Class Name
																			
	if (!RegisterClass(&wc))												// Attempt To Register The Window Class
	{
		MessageBox(NULL,"Failed To Register The Window Class.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;														// Return FALSE
	}																		
																			
	if (fullscreen)															// Attempt Fullscreen Mode?
	{																		
		DEVMODE dmScreenSettings;											// Device Mode
		memset(&dmScreenSettings,0,sizeof(dmScreenSettings));				// Makes Sure Memory's Cleared
		dmScreenSettings.dmSize=sizeof(dmScreenSettings);					// Size Of The Devmode Structure
		dmScreenSettings.dmPelsWidth	= width;							// Selected Screen Width
		dmScreenSettings.dmPelsHeight	= height;							// Selected Screen Height
		dmScreenSettings.dmBitsPerPel	= bits;								// Selected Bits Per Pixel
		dmScreenSettings.dmFields=DM_BITSPERPEL|DM_PELSWIDTH|DM_PELSHEIGHT;

		// Try To Set Selected Mode And Get Results.  NOTE: CDS_FULLSCREEN Gets Rid Of Start Bar.
		if (ChangeDisplaySettings(&dmScreenSettings,CDS_FULLSCREEN)!=DISP_CHANGE_SUCCESSFUL)
		{
			// If The Mode Fails, Offer Two Options.  Quit Or Use Windowed Mode.
			if (MessageBox(NULL,"The Requested Fullscreen Mode Is Not Supported By\nYour Video Card. Use Windowed Mode Instead?","NeHe GL",MB_YESNO|MB_ICONEXCLAMATION)==IDYES)
			{
				fullscreen=FALSE;											// Windowed Mode Selected.
			}
			else
			{
				// Pop Up A Message Box Letting User Know The Program Is Closing.
				MessageBox(NULL,"Program Will Now Close.","ERROR",MB_OK|MB_ICONSTOP);
				return FALSE;												// Return FALSE
			}																
		}																	
	}																		
																			
	if (fullscreen)															// Are We Still In Fullscreen Mode?
	{																		
		dwExStyle=WS_EX_APPWINDOW;											// Window Extended Style
		dwStyle=WS_POPUP;													// Windows Style
		ShowCursor(FALSE);													// Hide Mouse Pointer
	}																		
	else																	
	{																		
		dwExStyle=WS_EX_APPWINDOW | WS_EX_WINDOWEDGE;						// Window Extended Style
		dwStyle=WS_OVERLAPPEDWINDOW;										// Windows Style
	}																		
																			
	AdjustWindowRectEx(&WindowRect, dwStyle, FALSE, dwExStyle);				// Adjust Window To True Requested Size
																			
	// Create The Window													
	if (!(hWnd=CreateWindowEx(	dwExStyle,									// Extended Style For The Window
								"OpenGL",									// Class Name
								title,										// Window Title
								dwStyle |									// Defined Window Style
								WS_CLIPSIBLINGS |							// Required Window Style
								WS_CLIPCHILDREN,							// Required Window Style
								0, 0,										// Window Position
								WindowRect.right-WindowRect.left,			// Calculate Window Width
								WindowRect.bottom-WindowRect.top,			// Calculate Window Height
								NULL,										// No Parent Window
								NULL,										// No Menu
								hInstance,									// Instance
								NULL)))										// Dont Pass Anything To WM_CREATE
	{
		KillGLWindow();														// Reset The Display
		MessageBox(NULL,"Window Creation Error.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;														// Return FALSE
	}																		
																			
	static	PIXELFORMATDESCRIPTOR pfd=										// pfd Tells Windows How We Want Things To Be
	{																		
		sizeof(PIXELFORMATDESCRIPTOR),										// Size Of This Pixel Format Descriptor
		1,																	// Version Number
		PFD_DRAW_TO_WINDOW |												// Format Must Support Window
		PFD_SUPPORT_OPENGL |												// Format Must Support OpenGL
		PFD_DOUBLEBUFFER,													// Must Support Double Buffering
		PFD_TYPE_RGBA,														// Request An RGBA Format
		bits,																// Select Our Color Depth
		0, 0, 0, 0, 0, 0,													// Color Bits Ignored
		0,																	// No Alpha Buffer
		0,																	// Shift Bit Ignored
		0,																	// No Accumulation Buffer
		0, 0, 0, 0,															// Accumulation Bits Ignored
		16,																	// 16Bit Z-Buffer (Depth Buffer)  
		0,																	// No Stencil Buffer
		0,																	// No Auxiliary Buffer
		PFD_MAIN_PLANE,														// Main Drawing Layer
		0,																	// Reserved
		0, 0, 0																// Layer Masks Ignored
	};																		
																			
	if (!(hDC=GetDC(hWnd)))													// Did We Get A Device Context?
	{																		
		KillGLWindow();														// Reset The Display
		MessageBox(NULL,"Can't Create A GL Device Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;														// Return FALSE
	}																		
																			
	if (!(PixelFormat=ChoosePixelFormat(hDC,&pfd)))							// Did Windows Find A Matching Pixel Format?
	{																		
		KillGLWindow();														// Reset The Display
		MessageBox(NULL,"Can't Find A Suitable PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;														// Return FALSE
	}																		
																			
	if(!SetPixelFormat(hDC,PixelFormat,&pfd))								// Are We Able To Set The Pixel Format?
	{																		
		KillGLWindow();														// Reset The Display
		MessageBox(NULL,"Can't Set The PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;														// Return FALSE
	}																		
																			
	if (!(hRC=wglCreateContext(hDC)))										// Are We Able To Get A Rendering Context?
	{																		
		KillGLWindow();														// Reset The Display
		MessageBox(NULL,"Can't Create A GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;														// Return FALSE
	}																		
																			
	if(!wglMakeCurrent(hDC,hRC))											// Try To Activate The Rendering Context
	{																		
		KillGLWindow();														// Reset The Display
		MessageBox(NULL,"Can't Activate The GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;														// Return FALSE
	}																		
																			
	ShowWindow(hWnd,SW_SHOW);												// Show The Window
	SetForegroundWindow(hWnd);												// Slightly Higher Priority
	SetFocus(hWnd);															// Sets Keyboard Focus To The Window
	ReSizeGLScene(width, height);											// Set Up Our Perspective GL Screen
																			
	if (!InitGL())															// Initialize Our Newly Created GL Window
	{																		
		KillGLWindow();														// Reset The Display
		MessageBox(NULL,"Initialization Failed.","ERROR",MB_OK|MB_ICONEXCLAMATION);
		return FALSE;														// Return FALSE
	}																		
																			
	return TRUE;															// Success
}

//////////////////////////////////////////////////////////////////////////////
// Windows Callback Process
//////////////////////////////////////////////////////////////////////////////
LRESULT CALLBACK WndProc(	HWND	hWnd,									// Handle For This Window
							UINT	uMsg,									// Message For This Window
							WPARAM	wParam,									// Additional Message Information
							LPARAM	lParam)									// Additional Message Information
{																			
	switch (uMsg)															// Check For Windows Messages
	{																		
		case WM_ACTIVATE:													// Watch For Window Activate Message
		{																	
			if (!HIWORD(wParam))											// Check Minimization State
			{																
				active=TRUE;												// Program Is Active
			}																
			else															
			{																
				active=FALSE;												// Program Is No Longer Active
			}																
																			
			return 0;														// Return To The Message Loop
		}																	
																			
		case WM_SYSCOMMAND:													// Intercept System Commands
		{																	
			switch (wParam)													// Check System Calls
			{																
				case SC_SCREENSAVE:											// Screensaver Trying To Start?
				case SC_MONITORPOWER:										// Monitor Trying To Enter Powersave?
				return 0;													// Prevent From Happening
			}																
			break;															// Exit
		}																	
																			
		case WM_CLOSE:														// Did We Receive A Close Message?
		{																	
			PostQuitMessage(0);												// Send A Quit Message
			return 0;														// Jump Back
		}																	
																			
		case WM_KEYDOWN:													// Is A Key Being Held Down?
		{																	
			keys[wParam] = TRUE;											// If So, Mark It As TRUE
			return 0;														// Jump Back
		}																	
																			
		case WM_KEYUP:														// Has A Key Been Released?
		{																	
			keys[wParam] = FALSE;											// If So, Mark It As FALSE
			return 0;														// Jump Back
		}																	
																			
		case WM_SIZE:														// Resize The OpenGL Window
		{
			ReSizeGLScene(LOWORD(lParam),HIWORD(lParam));					// LoWord=Width, HiWord=Height
			return 0;														// Jump Back
		}
	}

	return DefWindowProc(hWnd,uMsg,wParam,lParam);							// Pass All Unhandled Messages To DefWindowProc
}

//////////////////////////////////////////////////////////////////////////////
// Main Windows Application Entry Point
//////////////////////////////////////////////////////////////////////////////
int WINAPI WinMain(	HINSTANCE	hInstance,									// Instance
					HINSTANCE	hPrevInstance,								// Previous Instance
					LPSTR		lpCmdLine,									// Command Line Parameters
					int			nCmdShow)									// Window Show State
{																			
	MSG		msg;															// Windows Message Structure
	BOOL	done=FALSE;														// Bool Variable To Exit Loop

	// Ask The User Which Screen Mode They Prefer
	if (MessageBox(NULL,"Would You Like To Run In Fullscreen Mode?", "Start FullScreen?",MB_YESNO|MB_ICONQUESTION)==IDNO)
	{
		fullscreen=FALSE;													// Windowed Mode
	}

	// Create Our OpenGL Window
	if (!CreateGLWindow("OpenGL AppWizard Framework",640,480,16,fullscreen))
	{
		return 0;															// Quit If Window Was Not Created
	}																		
																			
	while(!done)															// Loop That Runs While done=FALSE
	{																		
		if (PeekMessage(&msg,NULL,0,0,PM_REMOVE))							// Is There A Message Waiting?
		{																	
			if (msg.message==WM_QUIT)										// Have We Received A Quit Message?
			{																
				done=TRUE;													// If So done=TRUE
			}																
			else															// If Not, Deal With Window Messages
			{																
				TranslateMessage(&msg);										// Translate The Message
				DispatchMessage(&msg);										// Dispatch The Message
			}																
		}																	
		else																// If There Are No Messages
		{
			// Draw The Scene.  Watch For ESC Key And Quit Messages From DrawGLScene()
			if (active && keys[VK_ESCAPE])									// Active?  Was There A Quit Received?
			{																
				done=TRUE;													// ESC or DrawGLScene Signalled A Quit
			}																
			else															// Not Time To Quit, Update Screen
			{																
				DrawGLScene();												// Reduce Wasted Cycles While Minimized (Draw Scene)
				SwapBuffers(hDC);											// Swap Buffers (Double Buffering)
			}																
																			
			if (keys[VK_F1])												// Is F1 Being Pressed?
			{																
				keys[VK_F1]=FALSE;											// If So Make Key FALSE
				KillGLWindow();												// Kill Our Current Window
				fullscreen=!fullscreen;										// Toggle Fullscreen / Windowed Mode
				// Recreate Our OpenGL Window
				if (!CreateGLWindow("OpenGL AppWizard Framework",640,480,16,fullscreen))
				{
					return 0;												// Quit If Window Was Not Created
				}
			}
		}
	}

	// Shutdown
	KillGLWindow();															// Kill The Window
	return (msg.wParam);													// Exit The Program
}
